Liquid dispensing devices



June 27, 1957 G. G. GoDA ETAL 3,327,904

LIQUID DISPENSING DEVICES Filed Jan. 11, 196e 2 sheets-Sheet 1 ATTORNEYJune 27, 1967 G. G. GoDA ETAL 3,327,904

LIQUID DIsPENsING DEVICES Filed Jan. 11, 1966 2 Sheets-Sheet 2INVENTORS: G50/e E 6 600,4

oy o/v/ fa/v5 BY wav-w ATTORNEY 3,327,94 Patented .lune 27, 19673,327,904 LIQUID DISPENSING DEVICES George G. Gorla, New York, and RoyConiglione,

Maspeth, NY., assignors to Greiner Scientific Corporation, New York,N.Y.

Filed Jan. 11, 1966, Ser. No. 519,997 3 Claims. `(Cl. 222-309) Thisinvention relates to liquid measuring and dispensing devices. Moreparticularly the invention is concerned with burettes, pipettes,syringes and other devices for receiving and dispensing variablepredetermined volumes of liquid singly or repeatedly therefrom. Suchdevices are used in scientific and industrial laboratories, hospitals,medical; research, animal injections, bottling of pharmaceuticals and inother operations requiring quick and easy dispensing of known volumes ofliquid.

Such devices comprise a barrel and a plunger reciprocable therein,operable to draw a predetermined quantity of liquid into the barrel upona determined movement of the plunger in one longitudinal direction inthe barrel, followed by dispensing the liquid from the barrel uponreverse movement of the plunger.

An object of this invention is to provide in the class of devicesreferred to, a simple structure composed of a few easily assembled andeasily separable members.

Another object of the invention is to provide a measuring and dispensingdevice of the character described possessing mechanical simplicity andease of construction.

Another object of the invention is to provide a measuring and dispensingdevice of the character described, having resistance to chemicals andsolvents.

Another object of the invention is `to provide in a measuring anddispensing device of the character described, means for minimizingfriction between plunger and barrel during the reciprocating travel ofsaid plunger yet retaining the necessary liquid tightness and allowingeasy sliding reciprocating travel of the plunger for substantiallyfatigueless use of the device though the operator be dispensingtherefrom a preset volume of liquid repeatedly.

Other objects will be apparent in the fuller description which follows.

The invention comprises novel details of construction and novelcombinations and arrangements of parts, as will also appear from thefollowing description.

FIG. 1 is a side elevational view of a preferred embodiment of theinvention; the opposite side is substantially identical.

FIG. 2 is an enlarged front elevational view partly in section takenalong line 2 2 of FIG. 1; the opposite side is substantially identical.

FIG. 3 is an enlarged fragmentary view in central vertical section ofthe corresponding part of FIG. 2.

FIG. 4 is a view in horizontal section taken on line 4 4 of FIG. 3 inthe direction of the arrows.

FIG. 5 is an enlarged fragmentary View partly in section of thecorresponding part of FIG. 2.

FIG. 6 is an enlarged, exploded, perspective view of the correspondingparts of FIG. 2. The syringe barrel is shown separated.

FIG. 7 is an enlarged fragmented view in vertical section of thecorresponding parts of FIG. 2. The syringe barrel is shown inserted andlocked in place.

FIG. 8 is a view in horizontal section taken online 8 8 of FIG. 7 in thedirection of the arrows.

FIG. 9 is a view in horizontal section taken on line 9 9 of FIG. 7 inthe direction of the arrows.

FIG. lO is a front elevational view of the elements of FIG. 6 with thesyringe barrel flange inserted and in the process of being locked inplace by a quarter turn.

Referring now more particularly to the drawings, FIG. 2 is an enlargedfront elevational View partly in section taken along line 2 2 of FIG. l.Reference numeral 11 is a conventional commercially available tubularsyringe or barrel member made of glass or other transparent material.The upper open end of number 11 is provided with a liange 12 extendingoutwardly at right angle thereof and having two parallel sides and twocurved sides between them, better seen in FIG. 6. Graduations areprovided on the face of member 11 in conventional volumetric units.Member 11 terminates in a lower neck portion having an opening extendingtherethrough affording communication between a hypodermitc needle or thelike, which may be fitted thereto by conventional fittings, and thehollow interior of member 11. The neck portion may, if desired, befitted with conventional valve intake and discharge systems to permitrepetitive volume deliver; ies by the dispensing device from a reservoirof liquid to be dispensed. Reference numeral 8 indicates the engagementcollar member for barrel member 11 which it receives at fiange 12thereof and locks it in place by a quarter turn of barrel member 11 orcollar member 8.

References 6, 7, 8, 17 and 18 comprise an integral unit, preferably aplastic casting, polypropylene being favored, but other firm iiexiblepolymers resistant to environment of temperature, solvents and chemicalsmay be used.` Numeral 6 indicates finger grips, 7 a hollow tubularmember threaded internally to match external threads of rotatableadjusting nut 9, 8 an inverted cup-like engagement collar memberprovided with recessed parallel shoulders 18 and slots 19, the latter tofacilitate the iiexing of lip members 17. The heights of slots 19should' be slightly smaller than the thickness of barrel fiange 12, soas to permit flexing of lip members 17 and the locking operation. Thisintegral unit which functions to receive and retain the syringe barrelalso holds and aligns the volume adjusting and operating means of thisliquid measuring and dispensing device. This integral unit is furtherillustrated in FIG. 6` thru l0. Reference numerals 14, 1.5 and 16constitute the piston member comprised integrally of a neck portion 14with vertical matching recess therein to receive the lower end portionof hexagonal rod 5 which is securely held therein by locking pin 13, atapered shoulder 15 and a more yieldable piston closure portion 16slideably tightly fitting against the internal longitudinal wall ofsyringe barrel 11 and which under compression of the discharge stroke inoperationv is further pressed circumferentially outwardly to furthersecure and assure a liquid tight seal between piston closure portion 16and the inside wall of barrel 11. The bit of neck portion 20 whichextends downwardly below the bottom level of piston closure portion 16serves as a stop to protect closure portion 16 from being damaged byshock contact with inside floor of barrel 11 on discharge strokes of thepiston member. The entire piston member (14, 15, 16, 20) including thebit of neck portion or core can be made by different methods; forexample as a casting, o r by machining, or both. The bottom of thepiston closure portion 16 should be shortened so it will not extenddownwardly as far as core 20 does. Enlarged views of the piston memberare shown in FIGS. 3, 4 and 5. The composition of the piston member ispreferably Telion (Du Pont trademark for polyuorocarbon) but other rmpolymers are usable though generally less satisfactory as to heat,solvent and 4chemical stability or resistance, and as to low coeicientof friction and lower tendency to resist adherence of liquids to bedispensed. Such other polymers are polyethylene, nylon, polypropylene,rubber, silicone rubber, etc.

Elongated hexagonal driving member 5 is held at its lower end in amatching recess in the neck of piston member 14 and firmly retainedtherein by pin 13. This driving member passes slidably through amatching opening opening in volume adjusting nut 9 to transmit forcesapplied to vertically displace piston member 14 and serves as a key-likerotationally engaging member to drive volurne adjusting nut 9 verticallyagainst encircling ring 10 thereby moving piston 14 correspondingly toestablish and preset the dispensing volume. Driving member 5 extendsthru encircling piston return spring 4 and is held at its upper endrecessed in knurled rotatable knob 2 and firmly retained by screw 3.Resilient finger pad 1 is provided for comfort. The elongated drivingmember and its cooperating matching openings and recesses are obviouslynot limited to hexagonal cross section but any cross section thatfunctions to engage and rotate volume adjusting nut 9 when desired, iscontemplated. Elongated spiral spring 4 encircles rod 5, sits onhexagonal nut 9 and extends upward to contact and be restrained by theunderside of knob 2.

Reference numeral 10 indicates an incomplete encircling ring of metalpinched tightly against a circumferential groove in hexagonal rod 5,said ring having an outside diameter greater than the inside diameter ofvolume presetting position adjustable nut 9 and functioning as stopmember for the spring 4 actuated upward travel of said rod 5. Said nut 9is externally threaded to match internal threads of tubular member 7.

FIG. 6, the enlarged, exploded, perspective enlarged view of thecorresponding parts of FIG. 2, illustrates the syringe barrel member 11and engagement collar member 8 in disengaged arrangement.

FIG. 10 shows flange 12 of barrel member 11 inserted in engagementcollar member 8 and in the process of being placed in locked positionupon completion of a quarter turn of either member. This operationcauses lip members 17 to flex and then upon completion of the quarterturn, return to normal unflexed condition. In the locked positionunwanted rotation of barrel member 11 is prevented by parallel shoulders18 in close abutment to the parallel sides of flange 12 and downwarddisplacement of barrel member 11 is prevented by the inwardly extendingshoulders of lip members 17, which overlap the rounded sides of iiange12, FIG. 8. To permit separating barrel member 11 from engagement collarmember 8 the inwardly extending shoulders of lip members 17 should notextend inwardly beyond the outermost edges of the parallel sides ofiiange 12 when barrel 11 has been given a quarter turn to unlock fordisengaging barrel 11 at flange 12 thereof.

FIG. 7, a sectional view, shows barrel member 11 in locked positionwithin engagement collar member 8. Unwanted rotation of barrel member 11is prevented by parallel shoulders 18. FIG. 9, taken on line 9 9 of FIG.7 in the direction of the arrows further illustrates parallel shoulders18 of engagement collar member 8.

Engagement collar member 8 with its iiexing lip members 17 makes itquick and easy to assemble the dispensing device for use and todisassemble it for cleaning, autoclaving for sterilization, or replacingthe syringe barrel.

To operate this device, install on the terminating lower neck of portionbarrel 11 a conventional hypodermic needle, with valved intake anddis-charge system if desired. Rotate knob 2 until the bottom edge ofpiston member 16 is at the syringe barrel calibration corresponding tothe volume desired to be dispensed in one downward stroke of the plungerassembly. Having thus preset the dispensing volume desired, it persiststhrough repeated dispensings until reset for a different selectedvolume. Turning knob 2 rotates elongated key-like member 5 which in turnmoves volume adjusting nut 9 vertically to establish with ring 10 a topstop position for piston `member 14, to achieve the dispensing volumeselected. The bottom stop position for piston member 14 is, obviously,in all cases the inside bottom of barrel member 11. Immerse thehypodermic needle end in a reservoir of liquid to be dispensed. With twolingers of one hand under finger grips 6 press thumb down against ingerpad 1 until the piston member reaches its bottom stop position. Theoperator thereby overcomes the resistance of spring 4 and thus by thisdownward stroke empties barrel 11 of any liquid or air containedtherein. To clear the pertinent parts of air initially, may require morethan one stroke. Upon then releasing the thumb, spring 4 acts to returnpiston member 14 to its preset top stop position and thereby draws intobarrel 11 the liquid which on the subsequent complete downstroke of thepiston dispenses the volume of liquid selected in the presettingoperation. The dispensation of the preset volume can in this manner berepeated until reset for a diiferent selected volume.

Copending application Ser. No. 428,437, inventor George G. Goda, morefully illustrates and describes the means for presetting, at will, thevolume of liquid to be dispensed and retaining the setting for repeateddeliveries from a measuring and dispensing device of the characterdescribed.

Although an exemplary embodiment of the invention has been disclosed anddiscussed, it will be understood that other applications of theinvention are possible and that the embodiment dis-closed may besubjected to various changes, modifications and substitutions withoutdeparting from the spirit of the invention.

Integral unit 6, 7, 8, 17 and 18 functions as a flexible lockableengagement means for barrel member 11 and for retaining the pistonplunger assembly in operating arrangement in a common housing supportmember.

We claim:

1. A liquid dispensing device comprising a tubular vbarrel member withanged upward open end and downward discharge end, a piston reciprocablymounted in said barrel, means for variably presetting the volume ofliquid to be dispensed, means for plunging said piston downwardly insaid barrel member, spring means to bias said piston upwardly in saidbarrel member, stop means to limit said spring actuated upward travel ofsaid piston, a common housing and support member to retain said pistonin operating engagement provided with iiexible engagement means forsecuring and locking said barrel member, said engagement meanscomprising an inverted cup-like engagement collar slotted to formiiexible lip members provided with recessed parallel shoulders toprevent rotation of said locked barrel member and inwardly extendingshoulders on said lip members to prevent downward displacement of thelocked barrel member by overlapping same.

2. A device according to claim 1 in which said piston is comprised of anunderside annularly hollowed member provided with a central core and ayieldable piston c10- sure portion whose bottom edge is higher than thebottom edge of said core.

3. A device according to claim 1 in which the means for variablypresetting the volume of liquid to be dispensed comprises an elongatedmember lixedly retained at one end at said piston and extending upwardlytherefrom; means for rotating said elongated member; an externallythreaded adjusting nut with an opening slidably passing and rotatablyengageable by said elongated member; a wall internally threaded on saidcommon housing and a support member matching and engaging saidexternally threaded adjusting nut; and a protuberance on said elongatedmember upwards of said piston but downwards of said adjusting nut. 5

References Cited UNITED STATES PATENTS 2,530,909 11/1950 Riggs 222-309 X2,550,210 4/1951 Vance 222-158 X 10 Ruf 222-309 Hruskoci 222-309Hamilton 222-158 Burke 222-158 Simpson 222-386 X ROBERT B. REEVES,Primary Examiner.

N. L. STACK, Assistant Examiner.

1. A LIQUID DISPENSING DEVICE COMPRISING A TUBULAR BARREL MEMBER WITHFLANGED UPWARD OPEN END AND DOWNWARD DISCHARGE END, A PISTONRECIPROCABLY MOUNTED IN SAID BARREL, MEANS FOR VARIABLY PRESETTING THEVOLUME OF LIQUID TO BE DISPENSED, MEANS FOR PLUNGING SAID PISTONDOWNWARDLY IN SAID BARREL MEMBER, SPRING MEANS TO BIAS SAID PISTONUPWARDLY IN SAID BARREL MEMBER, STOP MEANS TO LIMIT SAID SPRING ACTUATEDUPWARD TRAVEL OF SAID PISTON, A COMMON HOUSING AND SUPPORT MEMBER TORETAIN SAID PISTON IN OPERATING ENGAGEMENT PROVIDED WITH FLEXIBLEENGAGEMENT MEANS FOR SECURING AND LOCKING SAID BARREL MEMBER, SAIDENGAGEMENT MEANS COMPRISING AN INVERTED CUP-LIKE ENGAGEMENT COLLARSLOTTED TO FORM FLEXIBLE LIP MEMBERS PROVIDED WITH RECESSED PARALLELSHOULDERS TO PREVENT ROTATION OF SAID LOCKED BARREL MEMBER AND INWARDLY